Concrete pumping swivel coupling apparatus with seal

Abstract

A swivel coupling apparatus includes a pair of aligned metal pipe sections having grooved outer ends for connecting to hoses and rigid pipes by releasable clamp units. A gasket is disposed between the smooth end faces and an outer clamp housing encircles the end portions to mechanically connect the pipe sections. The pipe sections have outer shoulders with inclined clamp walls. The clamp housing includes a pair of semi-circular members having bolt clamping lugs for drawing the members onto the shoulders. The members having outer side clamp legs defining a cavity. A central rectangular spacer projects partially into the cavity for location between the outer portion of the end faces. The cavity has annular base walls between the spacer and side legs aligned with and outwardly spaced from the outer peripheral walls of the shoulders. Grease fittings to the opposite sides of the spacer provide for introducing of grease into the free space. The spacer has a smooth inner wall forming a backing for the gasket. The ring gasket is formed with a rectangular outer body and inner flared side lips with a curved base wall on the inner face to define a pressure chamber. The pumped concrete moves into the chamber and acts on the side lips to increase the sealing effect of the gasket.

We claim: 
     
       1. A sealing gasket adapted to be clamped between the ends of a pair of relatively rotatable rigid pipe members, comprising a continuous gasket member having an outer body portion and integral outwardly flared inner side lips, said sealing gasket having an annular recess located between said lips and having a depth substantially less than said sealing lips, said lips being adapted to be deflected inwardly less than the width of said body portion to define a gap adjacent the sidewalls, a rigid spacer member located to the back side of body, said spacer member having a width in excess of said body and less than the distance between the side lips whereby said pipe member may be disposed abutting the ends of the spacer members to define the limits of the deflection of said sealing lips. 
     
     
       2. The sealing gasket of claim 1 wherein said outer body portion is a substantially rectangular body having substantially parallel sidewalls from which said side lips extend. 
     
     
       3. A sealing gasket adapted to be clamped between the ends of a pair of relatively rotatable rigid pipe members having a spacer for holding said pipe members with a selected space between the ends thereof, comprising a continuous gasket member having an outer body portion and integral outwardly flared inner side sealing lips, said sealing gasket having an annular shallow recess located between said lips and having a depth substantially less than said sealing lips, said lips being adapted to be deflected inwardly less than the width of said body portion to define a gap adjacent the sidewalls, said body having a width less than said spacer and said side sealing lips having an undeflected extent greater than the spacer whereby said pipe members are disposed abutting the ends of the spacer and defining the limits of the deflection of said sealing lips with the ends of the pipe members spaced from said body portion of said sealing gasket. 
     
     
       4. The sealing gasket of claim 3 wherein said body portion includes an outer rectangular body having parallel sidewalls and said annular shallow recess is a circular peripheral wall.